Magnetic cleaning system and method for cleaning ferromagnetic objects

ABSTRACT

A cleaning system and a method for cleaning a surface of a ferromagnetic object are disclosed. Accordingly, to an example configuration, the cleaning system includes a device body that comprises a magnetic system that urges an abrasive layer against the surface of the ferromagnetic object by a magnetic force. In at least some examples, the magnetic force provided by the magnetic system is adjustable to achieve a target magnetic force for cleaning the surface.

CROSS REFERENCE TO RELATED APPLICATIONS

This application incorporates herein by reference for all purposes the entire contents of U.S. patent application Ser. No. ______, filed ______, titled “SCRAPER-BASED MAGNETIC CLEANING SYSTEM AND METHOD FOR CLEANING FERROMAGNETIC OBJECTS”, and assigned docket number 19-1894-US-NP.

FIELD

The invention relates generally to cleaning a surface of a ferromagnetic object with an abrasive layer that is urged against the surface of the ferromagnetic object by a magnetic force.

BACKGROUND

Composite materials may be formed during layup operations using cure tooling that incorporate ferromagnetic materials, such as Invar—a nickel-iron alloy relied upon for its low coefficient of thermal expansion. Resin and other contaminants may build up on cure tooling from use, which may require periodic cleaning of cure tooling surfaces. Aeronautical components formed of composite materials including wing spars, stringers, skin panels, etc. may use cure tooling of relatively large dimensions and/or complex geometry that may pose challenges for manufacturing personnel to consistently and adequately clean between layup operations.

SUMMARY

According to an example of the present disclosure, a cleaning system for cleaning a surface of a ferromagnetic object comprises a device body defining a cleaning face having an abrasive layer configured for selective placement against the surface of the ferromagnetic object. The device body comprises a magnetic system configured to generate a magnetic field of a strength that is adjustable in relation to the abrasive layer. The magnetic field generated by the magnetic system is configured to urge the abrasive layer against the surface of the ferromagnetic object with a magnetic force corresponding to the strength of the magnetic field.

According to another example of the present disclosure, a method for cleaning a surface of a ferromagnetic object comprises selecting a cleaning system that includes a device body comprising a magnetic system configured to generate a magnetic field. The device body is coupled to a cleaning face having an abrasive layer configured for selective placement against the surface of the ferromagnetic object. The method further comprises placing the abrasive layer in contact with the surface of the ferromagnetic object with the magnetic field generated by the magnetic system urging the abrasive layer against the surface of the ferromagnetic object with a magnetic force corresponding to a strength of the magnetic field. The method further comprises moving the device body relative to the surface of the ferromagnetic object while the abrasive layer is in contact with the surface.

According to another example of the present disclosure, a cleaning system for cleaning a surface of a ferromagnetic object comprises a device body forming a shroud mountable to a power tool that includes a power take-off element. The shroud defines an interior region that is configured to accommodate and partially surround the power take-off element. The shroud comprises a magnetic system configured to generate a magnetic field urging a distal end of the power-take-off element toward the surface of the ferromagnetic object with a magnetic force corresponding to a strength of the magnetic field.

The example features and techniques discussed in the Summary can be provided independently in various embodiments or may be combined in yet other embodiments, further details of which are described by the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically depicts an example cleaning system for cleaning a surface of a ferromagnetic object.

FIGS. 2A and 2B depict an example of a first configuration of the cleaning system of FIG. 1, including a device body defining one or more receptacles that accommodate magnets in a rear-loading configuration.

FIG. 3 depicts an example of a second configuration of the cleaning system of FIG. 1, including a device body defining one or more mounts that accommodate magnets in a rear-mounting configuration.

FIGS. 4A and 4B depict an example of a third configuration of the cleaning system of FIG. 1, including a device body defining one or more receptacles that accommodate magnets in a side-loading configuration.

FIGS. 5A, 5B, and 5C depict an example of a fifth configuration of the cleaning system of FIG. 1, including a device body defining one or more receptacles that accommodate magnets in a bottom-loading configuration.

FIG. 6 depicts an example of a sixth configuration of the cleaning system of FIG. 1, including one or more electromagnets.

FIGS. 7A-7C depict example configurations of magnets in relation to the abrasive layer of the cleaning system of FIG. 1.

FIGS. 8A, 8B, and 8C depict example device body configurations that provide a non-planar cleaning face.

FIGS. 9A and 9B depict an example configuration of the device body of the cleaning system of FIG. 1, including a guide portion.

FIGS. 10A and 10B depict a cleaning system for cleaning a surface of a ferromagnetic object using a power tool.

FIGS. 11A and 11B depict example configurations for moving the cleaning system of FIG. 1.

FIG. 12 is a flow diagram depicting an example method for cleaning a surface of a ferromagnetic object.

FIGS. 13 and 14 depict example abrasive layers that are permeable by ferromagnetic particulate or contaminant particulate produced by cleaning a surface of a ferromagnetic object.

DETAILED DESCRIPTION

A cleaning system and a method for cleaning a surface of a ferromagnetic object are disclosed. Accordingly, to an example configuration, the cleaning system includes a device body that comprises a magnetic system that generates a magnetic field that urges an abrasive layer against the surface of the ferromagnetic object by a magnetic force. In at least some examples, the magnetic field generated by the magnetic system is adjustable in relation to the abrasive layer to achieve a target magnetic force for cleaning the surface of the ferromagnetic object. The ability to adjust the magnetic field and the corresponding magnetic force urging the abrasive layer against the surface of the ferromagnetic object may provide a more consistent cleaning rate, with less user fatigue as compared to hand-operated cleaning tools that may rely exclusively on user-applied forces, particularly for cure tooling of large and/or complex geometries. By achieving a more consistent cleaning rate across a surface of a ferromagnetic object through magnetic interaction, manufacturing personnel may be better able to balance the competing goals of removing resin and other contaminants from the surface of the ferromagnetic object while also minimizing wear to the surface from abrasives used during the cleaning operation. Furthermore, ferromagnetic particulate generated from ferromagnetic surfaces of ferromagnetic objects during the cleaning operation may be collected by the magnetic system through magnetic interaction, thereby reducing the presence of free ferromagnetic particulate within the manufacturing environment.

FIG. 1 schematically depicts an example cleaning system 100 for cleaning a surface 102 of a ferromagnetic object 104. Surface 102 may include a ferromagnetic surface of ferromagnetic object 104 or may include a non-ferromagnetic surface of a non-ferromagnetic layer overlaying a ferromagnetic portion of ferromagnetic object 104.

Cleaning system 100 includes a device body 110 defining a cleaning face 112 having an abrasive layer 120. Device body 110 comprises a magnetic system 130 configured to generate a magnetic field. The magnetic field generated by magnetic system 130 is configured to urge abrasive layer 120 against surface 102 of ferromagnetic object 104 with a magnetic force 132 corresponding to a strength of the magnetic field.

To clean surface 102, an exterior-facing surface 122 of abrasive layer 120 may be selectively placed in contact with a region of the surface to be cleaned while the magnetic field generated by magnetic system 130 urges the abrasive layer against the surface of ferromagnetic object 104 with magnetic force 132. Device body 110 may be moved by hand or by machine while exterior-facing surface 112 of abrasive layer 120 is in contact with surface 102, including translating, rotating, and/or vibrating the device body and its abrasive layer in relation to the surface.

In at least some examples, device body 110 may include one or more handles represented schematically at 114 in FIG. 1 to enable a user to manipulate device body 110 by hand. One or more handles 114 of device body 110 may take various forms, including a handlebar, a knob, a boom handle, a flexible loop, etc. In further examples, the one or more handles 114 and/or may be omitted or may be replaced by a coupling (e.g., a mechanical coupling) to a machine, such as described in further detail with reference to FIG. 11A.

In at least some examples, abrasive layer 120 includes a pad formed of abrasive material, such as silicon carbide, aluminum oxide, or talc abrasive mineral, as non-limiting examples. For example, abrasive layer 120 may take the form of a disposable pad that entraps particulate produced by cleaning surface 102. An interior-facing surface 124 of abrasive layer 120 may be removably mounted to cleaning face 112 using a variety of suitable techniques, including hook and loop, adhesive, and/or mechanical fasteners. In the context of hook and loop, one of the interior-facing surface 124 or cleaning face 112 may include a matrix of loops and the other of the interior-facing surface 124 or cleaning face 112 may include a matrix of hooks. Mechanical fasteners may be recessed beneath exterior-facing surface 122 of abrasive layer 120 or may be provided along one or more exterior edges of the abrasive layer. Additionally, aspects of abrasive layer 120 are described in further detail with reference to FIGS. 13 and 14.

Magnetic system 130 may include one or more magnets. Example configurations of magnetic system 130 are described in further detail with reference to FIGS. 2-7, and FIG. 10. Briefly, the one or more magnets of magnetic system 130 may include permanent magnets that generate a persistent magnetic field and/or electromagnets that generate a magnetic field responsive to electrical current being supplied to the electromagnets. In at least some examples, device body 110 may be partially or wholly formed from a permanent magnet material that generates a persistent magnetic field for magnetic system 130.

In further examples, device body 110 may be formed from a non-magnetic and/or non-ferromagnetic material and may define one or more receptacles or mounts that accommodate one or more magnets of magnetic system 130. As non-limiting examples, device body 110 may be formed from one or more of a polymer, wood, ceramic, non-ferromagnetic metal, or other suitable material. A chemical resistant plastic, for example, may be used for device body 110 where cleaning system 100 is used in combination with cleaning solutions or solvents, such as acetone.

In at least some examples, magnetic system 130 is configured to generate a magnetic field having a strength that is adjustable by a user or programmatically adjustable by a machine to thereby achieve a target magnetic force that urges abrasive layer 120 against surface 102. In at least some examples, once the strength of the magnetic field generated by magnetic system 130 has been adjusted to a target magnetic field strength, the magnetic field generated by magnetic system 130 and the corresponding magnetic force 132 with respect to a surface of a ferromagnetic object remain constant, thereby providing a consistent cleaning rate across the surface.

Cleaning system 100 is depicted in simplified form in FIG. 1. Accordingly, cleaning system 100 may take other suitable forms as described in further detail with reference to the example configurations of FIGS. 2-11. Furthermore, surface 102 and ferromagnetic object 104 are depicted schematically in FIG. 1. Accordingly, surface 102 and ferromagnetic object 104 may take other shapes or forms.

FIGS. 2A and 2B depict an example of a first configuration of cleaning system 100. Within FIGS. 2A and 2B, device body 110-2 and magnetic system 130-2 correspond to non-limiting examples of device body 110 and magnetic system 130 of FIG. 1, respectively. FIG. 2A depicts device body 110-2 from a top view in which abrasive layer 120 is located on an opposite side of the device body, and FIG. 2B depicts device body 110-2 from a side view of section 230 of FIG. 2A.

In this first configuration, device body 110-2 defines one or more receptacles 210, 212, 214, 216, etc., each receptacle accommodating one or more respective magnets 220, 222, 224, 226, etc. Magnets 220-226 may take the form of permanent magnets that generate a persistent magnetic field. Magnets 220-226 may form a first set 240 that collectively urges abrasive layer 120 against a surface of a ferromagnetic object by magnetic force 132. Magnets may be press fit into receptacles of the device body, in at least some examples. Alternatively, mechanical fasteners and/or adhesives may be used to secure magnets within receptacles of the device body. While FIGS. 2A and 2B depict each receptacle accommodating an individual magnet, in at least some examples, each receptacle may accommodate two or more magnets.

Furthermore, in at least some examples, receptacles 210-216 and corresponding magnets (e.g., 220-226) accommodated by the receptacles may be symmetrically arranged about a midplane 250 of the device body, thereby providing an evenly distributed magnetic force along the cleaning face of the device body. Additionally, or alternatively, two, three or more magnets and their respective receptacles may be distributed at regular intervals along an axis of the cleaning face of the device body, thereby providing an evenly distributed magnetic force along the cleaning face.

As depicted in FIG. 2B, one or more magnets of first set 240 may be removable from its respective receptacle as indicated at 260 with respect to example magnet 220. Removal of a magnet from the device body of cleaning system 100 reduces magnetic force 132 that urges abrasive layer 120 against a surface of a ferromagnetic object. Conversely, adding a magnet to the device body of cleaning system 100 increases magnetic force 132 that urges abrasive layer 120 against a surface of a ferromagnetic object.

In at least some examples, magnetic system 130 may include a plurality of magnets that generate magnetic fields of a variety of different strengths. For example, magnetic system 130-2 of FIG. 2B may further include one or more magnets forming a second set 242 that may replace one or more magnets of first set 240 in a corresponding receptacle, as indicated schematically at 244. The magnets of second set 242 may each generate a magnetic field of a strength that is stronger or weaker than the magnets of first set 240. By replacing some or all magnets of first set 240 with some or all magnets of second set 242, magnetic force 132 that urges abrasive layer 120 against a surface of a ferromagnetic object may be increased or decreased.

The first configuration of cleaning system 100 described with reference to FIGS. 2A and 2B may be referred to as a rear-loading configuration in which one or more magnets may be selectively inserted into and removed from receptacles formed within a rear face 270 of the device body that opposes cleaning face 112. FIG. 3 depicts an example of a second configuration of cleaning system 100 in which device body 110-3 defines one or more mounts 310, 312, 314, 316, etc. located along a rear face 370 of the device body that accommodate one or more magnets 320, 322, 324, 326, etc. of magnetic system 130-3. The second configuration of FIG. 3 may be referred to as a rear-mounting configuration.

FIG. 3 depicts device body 110-3 from a side view. Within FIG. 3, device body 110-3 and magnetic system 130-3 correspond to non-limiting examples of device body 110 and magnetic system 130 of FIG. 1, respectively. Magnets 320-326 may correspond to one of multiple sets of magnets of the magnet system, such as previously described with reference to sets 240 and 242 of FIG. 2. Magnets 320-326 may take the form of permanent magnets that generate a persistent magnetic field to urge abrasive layer 120 against a surface of a ferromagnetic object by magnetic force 132.

In at least some examples, mounts 310-316 and corresponding magnets (e.g., 320-326) accommodated by the mounts may be symmetrically arranged about a midplane 350 of the device body, thereby providing an evenly distributed magnetic force along the cleaning face of the device body. Additionally, or alternatively, two, three or more magnets and their respective mounts may be distributed at regular intervals along an axis of the cleaning face of the device body, thereby providing an evenly distributed magnetic force along the cleaning face.

Features associated with the mounting of example magnet 320 to mount 310 of device body 110-3 are depicted in FIG. 3 in further detail. For example, magnet 320 may be mounted to device body 110-3 using a fastener component 330 that cooperates with a corresponding fastener component 332 of mount 310 located on an opposite side of magnet 320. In this example, fastener component 330 takes the form of a male-side fastener, such as a bolt or a screw. It will be understood that fastener component 330 may take other suitable forms, including a female-side fastener, such as a threaded nut or enclosure lid. For example, in the case where fastener component 330 or 332 takes the form of a male-side fastener, the other of fastener component 330 or 332 make take the form of a female-side fastener. In the example depicted in FIG. 3, fastener component 332 takes the form of a tapped receptacle formed in device body 110-3. In at least some examples, magnet 320 may include a through-passage 334 through which a male-side fastener of fastener component 330 or 332 may pass, as indicated at 336. In further examples, an enclosure lid may be used to secure some or all of the magnets to the device body, such as via one or more fasteners.

FIGS. 4A and 4B depict an example of a third configuration of cleaning system 100. In this third configuration, one or more magnets may be inserted into and removed from one or more receptacles formed within a side of the device body, which may be referred to as a side-loading configuration. Within FIGS. 4A and 4B, device body 110-4 and magnetic system 130-4 correspond to non-limiting examples of device body 110 and magnetic system 130 of FIG. 1, respectively. FIG. 4A depicts device body 110-4 through a section 430 of FIG. 4B from a top view, and FIG. 4B depicts device body 110-4 from a side view.

In this third configuration, device body 110-4 defines one or more receptacles 410, 412, 414, 416, etc., each receptacle accommodating one or more respective magnets 420, 422, 424, 426, etc. Magnets 420-426 may correspond to one of multiple sets of magnets of the magnet system, such as previously described with reference to sets 240 and 242 of FIG. 2. Magnets 420-426 may take the form of permanent magnets that generate a persistent magnetic field to urge abrasive layer 120 against a surface of a ferromagnetic object by magnetic force 132.

As depicted in FIG. 4B, one or more of magnets 420-426 may be removable from its respective receptacle as indicated at 432 with respect to example magnet 420. In at least some examples, receptacles 410-416 and corresponding magnets (e.g., 420-426) accommodated by the receptacles may be symmetrically arranged about a midplane 450 of the device body, thereby providing an evenly distributed magnetic force along the cleaning face of the device body. Additionally, or alternatively, two, three or more magnets and their respective receptacles may be distributed at regular intervals along an axis of the cleaning face, thereby providing an evenly distributed magnetic force along the cleaning face.

While FIGS. 4A and 4B depict an example of a side-loading configuration and FIG. 3 depicts an example of a rear-mounting configuration, in further examples, one or more magnets may be mounted to one or more sides of the device body via one or more fasteners. This fourth configuration of magnetic system 130 may be referred to as a side-mounting configuration and may enable one or more of these magnets to be mounted upon and removed from the device body, such as previously described with reference to the mounts and fasteners of FIG. 3.

FIGS. 5A, 5B, and 5C depict an example of a fifth configuration of the cleaning system of FIG. 1, including a device body defining one or more receptacles that accommodate magnets in a bottom-loading configuration. In this fifth configuration, one or more magnets may be inserted into and removed from one or more receptacles formed within a bottom of the device body corresponding to a cleaning face to which an abrasive pad or layer may be mounted. Within FIGS. 5A, 5B, and 5C, device body 110-5 and magnetic system 130-5 correspond to non-limiting examples of device body 110 and magnetic system 130 of FIG. 1, respectively. FIG. 5A depicts an exploded view of device body 110-5 and magnetic system 130-5 through section 532 of FIG. 5C from a side view, FIG. 5B depicts an assembled view of device body 110-5 and magnetic system 130-5 through section 532 from the side view, and FIG. 5C depicts an assembled view of device body 110-5 and magnetic system 130-5 through section 530 of FIG. 5B.

In this fifth configuration, device body 110-5 is formed from an upper portion 502, and one or more lower portions 504, 506, etc. In an example, lower portions 504 and 506 may take the form of cradles or doors that, in combination with upper portion 502, respectively form receptacles 520, 522, etc. accommodating one or more respective magnets 510, 512, etc. of magnetic system 130-5. Magnets 510 and 512 may correspond to one of multiple sets of magnets of the magnet system, such as 510 and 512 may take the form of permanent magnets that generate a persistent magnetic field to urge abrasive layer 120 against a surface of a ferromagnetic object by magnetic force 132.

As depicted in FIG. 5B, upper portion 502, and lower portions 504 and 506 may collectively define cleaning face 112 to which abrasive layer 120 is mounted. In at least some examples, lower portions 504 and 506 may be secured to upper portion 502 via one or more fasteners, depicted schematically in FIG. 5B at 540 and 542, respectively. As depicted in FIG. 5A, one or more of magnets 510 and 512 may be removable from its respective receptacle. In at least some examples, receptacles 520 and 522, and corresponding magnets (e.g., 510 and 512) accommodated by the receptacles may be symmetrically arranged about a midplane 550 of the device body, thereby providing an evenly distributed magnetic force along the cleaning face of the device body. Additionally, or alternatively, two, three or more magnets and their respective receptacles may be distributed at regular intervals along an axis of the cleaning face, thereby providing an evenly distributed magnetic force along the cleaning face.

In at least some examples, a positioning of one or more permanent magnets accommodated by the device body may be adjusted in relation to the abrasive layer to thereby adjust a strength of the magnetic field in relation to the abrasive layer. Referring again to the configurations of FIGS. 2A, 2B, and 3 as examples, a non-magnetic spacer may be inserted into one or more of receptacles 210-216 or placed upon a mounting surface before one or more of magnets 210-216 are inserted into the receptacles or mounted to the device body to increase a distance between the magnets and abrasive layer 120, thereby reducing the corresponding magnetic force urging the abrasive layer against the surface of the ferromagnetic object. Conversely, the non-magnetic spacer may be removed from the receptacle or mounting surface to reduce a distance between a magnet of that receptacle or mount and the abrasive layer, thereby increasing the corresponding magnetic force urging the abrasive layer against the surface. Referring again to the configuration of FIG. 3 as another example, fastener portions 330 and/or 332 may cooperate with magnet 320 to increase or decrease a distance of the magnet from abrasive layer 120. For example, magnet 320 may include threads (e.g., at through-passage 334) that mate with corresponding threads of one or more of fastener portions 330 and/or 332, thereby enabling the distance of the magnet from abrasive layer 120 to be increased or decreased by rotation of the magnet relative to the fastener portion. As yet another example, a plurality of magnets of different strengths may be placed within or upon a receptacle or mount in stacked configuration, and the order of the plurality of magnets within the stacked configuration may be changed to increase or decrease the strength of the magnetic field at the abrasive layer.

FIG. 6 depicts an example of a fifth configuration of cleaning system 100 in which the magnetic system includes one or more electromagnets 620, 622, 624, 626, etc. FIG. 6 depicts device body 110-6 from a side view through a section of the device body. Within FIG. 6, device body 110-6 and magnetic system 130-6 correspond to non-limiting examples of device body 110 and magnetic system 130 of FIG. 1, respectively.

In the example depicted in FIG. 6, electromagnets 620-626 are disposed within device body 110-6. However, in other examples, electromagnets 620-626 may be mounted upon an exterior of device body 110-6, such as previously described with respect to the mounts of FIG. 3, for example. In at least some examples, electromagnets 620-626 may be symmetrically arranged about a midplane 650 of the device body, thereby providing an evenly distributed magnetic force along the cleaning face of the device body. Additionally, or alternatively, two, three or more of electromagnets 620-626 may be distributed at regular intervals along an axis of the cleaning face of the device body, thereby providing an evenly distributed magnetic force along the cleaning face.

Electromagnets 620-626 may form part of an electronic circuit 600 of magnet system 130-6. Electronic circuit 600 may further include an electrical power source 610 that supplies electrical energy (e.g., electrical current) to electromagnets 620-626 via electrically conductive pathways 612 and 614. Electrical power source 610 may include one or more batteries and/or may interface with an external power supply via an electrical outlet.

Electronic circuit 600 may further include an electronic controller 616 that varies electrical current supplied to the one or more electromagnets 620-626 from electrical power source 610 responsive to a user input to generate a magnetic field via the one or more electromagnets having an adjustable strength. For example, electronic controller 616 may include a control interface 618 by which a user input may be received, enabling a user to set a strength of the magnetic field produced by electromagnets 620-626 to achieve a target magnetic field and corresponding magnetic force. Control interface 618 may include one or more buttons, switches, sliders, graphical user interfaces, etc. operable by a user to vary the electrical power and/or current supplied to the electromagnets from the electrical power source 610 via electronic controller 616. Alternatively, or additionally, electronic controller 616 may programmatically adjust the magnetic field generated by the electromagnets to achieve a target magnetic force. In at least some examples, once the magnetic field produced by the electromagnets and the corresponding magnetic force 132 have been set by adjusting a strength of the magnetic field, the magnetic field may be maintained at a constant strength, thereby enabling the surface of the ferromagnetic object to be consistently cleaned at an appropriate rate through manipulation of the device body and its abrasive layer.

The example configurations described with reference to FIGS. 2-6 may be used individually or combination to obtain a variety of magnetic system configurations that include permanent magnets and/or electromagnets. For example, FIGS. 7A-7C depict additional configurations of magnets in relation to abrasive layer 120.

FIG. 7A depicts an example configuration of magnets 710 in relation to abrasive layer 120 as viewed along an axis that is orthogonal to a plane of exterior-facing surface 122 of abrasive layer 120. In this example configuration, magnets 710 are arranged in a two-dimensional matrix that is symmetric about a first midplane 720 and a second midplane 722 that are orthogonal to each other. As previously described with reference to FIGS. 2-6, a symmetric configuration of magnets (e.g., 710) about one or more midplanes of a device body may provide an even distribution of magnetic force along abrasive layer 120 in one or two dimensions.

FIG. 7B depicts an example configuration of magnets 730 in relation to abrasive layer 120, as viewed along an axis that is orthogonal to a plane of exterior-facing surface 122 of abrasive layer 120. In this example, magnets 730 span abrasive layer 120 along a first axis (e.g., oriented along midplane 742), and are symmetrically arranged about both a first midplane 740 and a second midplane 742 that are orthogonal to each other. This symmetric configuration of magnets (e.g., 730) about one or more midplanes of a device body may again provide an even distribution of magnetic force across abrasive layer 120 in one or more two dimensions.

FIG. 7C depicts an example configuration in which one or more sheet magnets 750 span a portion of or the entirety of abrasive layer 120. In examples where one or more magnets 750 span the entirety of abrasive layer 120, an even distribution of magnetic force may be provided across abrasive layer 120 in two dimensions.

Within the preceding examples of FIGS. 1-6, cleaning face 112 is depicted as a planar cleaning face. However, cleaning face 112 may take other suitable forms for cleaning ferromagnetic objects having curved surfaces. FIGS. 8A, 8B, and 8C depict example device body configurations that provide a non-planar cleaning face.

FIG. 8A depicts example device body 110-8A that defines a concave cleaning face 112-8A to which abrasive layer 120 may be mounted that is suitable for cleaning a convex surface of a ferromagnetic object. Magnetic system 130-8A may include one or more magnets (e.g., 810, 812, etc.) associated with respective regions (e.g., portions of the cleaning face) of device body 110-8A to provide a distribution of magnetic force across concave cleaning face 112-8A.

FIG. 8B depicts example device body 110-8B that defines a convex cleaning face 112-8B to which abrasive layer 120 may be mounted that is suitable for cleaning a concave surface of a ferromagnetic object. Magnetic system 130-8B may include one or more magnets (e.g., 810, 812, etc.) associated with respective regions of device body 110-8B to provide a distribution of magnetic force across convex cleaning face 112-8B.

In at least some examples, any of the device bodies disclosed herein may be flexible to allow cleaning face 112 and abrasive layer 120 to wholly or partially conform to a shape of a surface of a ferromagnetic object to be cleaned by the cleaning system. For example, FIG. 8C depicts an example device body 110-8C having a first shape (e.g., planar cleaning face 112) that conforms to example surface 102-8C of example ferromagnetic object 104-8C upon magnetic force 132 of magnetic system 130 urging the device body and abrasive layer against the surface. Flexibility of the device body of cleaning system 100 may be obtained by a configuration of the device body (e.g., a device body having a thickness in a dimension normal to the abrasive layer and/or surface that enables the device body to flex under an applied force) and/or a material from which the device body is formed.

FIGS. 9A and 9B depict another example configuration of device body 110 of cleaning system 100. FIG. 9A depicts a view of device body 110-9 from a side containing abrasive layer 120, and FIG. 9B depicts a view of device body 110-9 from a rear side with abrasive layer 120 facing toward example surface 102-9 of example ferromagnetic object 104-9. Within FIGS. 9A and 9B, device body 110-9 corresponds to a non-limiting example of device body 110 of FIG. 1.

Device body 110-9 in this example further includes a guide portion 910 projecting outward from a first edge 912 of cleaning face 112 to form an interior-facing corner 914 with the cleaning face. While FIG. 9A depicts guide portion 910 extending continuously along the entirety of first edge 912, it will be understood that guide portion 910 may take other forms including two or more guide portion sections spaced apart from each other along first edge 912, and so forth.

A face 916 of guide portion 910 may be placed in contact with an edge of surface 102-9 as indicated at 920 in FIG. 9B, for example to limit cleaning of surface 102-9 by abrasive layer 120 to an edge region 922. Accordingly, an interior region 924 of surface 102-9 may be precluded from contact by abrasive layer 120 by the use of guide portion 910. In at least some examples, face 916 of guide portion 910 may include a non-abrasive surface and/or low friction layer (e.g., Teflon or Armarlon tape) to reduce cleaning and/or wear to an edge of a surface. In further examples, guide portion 910 or device body 110-9 may be formed of a non-abrasive, low-friction material, such as Teflon.

FIG. 9B further depicts an example of magnetic force 132 generated by magnetic system 130 in relation to surface 102-9. Device body 110-9 may comprise magnetic system 130 having any of the various configurations disclosed herein. Device body 110-9 may further include one or more handles and/or other features to enable the device body to be moved by hand or by machine during cleaning of a surface of a ferromagnetic object.

FIGS. 10A and 10B depict a cleaning system 1000 for cleaning a surface of a ferromagnetic object, such as example surface 102 of FIG. 1. Cleaning system 1000 may incorporate at least some of the features previously described with reference to cleaning system 100 of FIG. 1, including abrasive layer 120 and magnetic system 130-10.

In contrast to cleaning system 100 of FIG. 1, cleaning system 1000 includes a device body forming a shroud 1010 that is mountable to a tool body 122 of a power tool 1020 in a pre-defined configuration. As an example, one or more fasteners may be used to mount shroud 1010 to tool body 1022. Alternatively, or additionally, shroud 1010 may be press fit onto tool body 1022. Power tool 1020 further includes a power take-off element 1024 that is operable to move relative to tool body 1022. Tool body 1022 may further include one or more handles 1026 that enable a user to operate the power tool by hand. In further examples, one or more handles 1026 may be omitted, and mechanical couplings may be used to manipulate cleaning system 1000, such as described in further detail with reference to FIG. 11A. Power tool 1020 may include an electrically-powered or air-powered tool, such as an orbital sander, belt sander, drill, etc., as non-limiting examples.

Shroud 1010 defines an interior region 1012 that is configured to accommodate and at least partially surround power take-off element 1024, while enabling a distal end 1028 of power take-off element 1024 to be accessible via an opening 1014 formed by a distal end 1016 of the shroud. Power take-off element 1024 may include abrasive layer 120 mounted to distal end 1028 or an extension thereof that contacts surface 102 when distal end 1016 of shroud 1010 surrounding opening 1014 is placed against the surface. Upon operation of power take-off element 1024, abrasive layer 120 may translate, rotate, and/or vibrate to clean surface 102.

Shroud 1010 further comprises magnetic system 130-10 as a non-limiting example of previously described magnetic system 130. Magnetic system 130-10 is configured to generate a magnetic field urging abrasive layer 120 mounted upon distal end 1028 of power-take-off element 1024 toward surface 102 of ferromagnetic object 104 with magnetic force 132 corresponding to a strength of the magnetic field. Magnetic force 132 provided by shroud 1010 through magnetic interaction with a ferromagnetic object may reduce movement of tool body 1022 caused by operation of power take-off element 1024, which in turn may reduce propagation of vibrations through tool body 1022 to a person or machine operating power tool 1020. Accordingly, fatigue or injury to human or machine operators through prolonged use of power tool 1020 may be reduced or eliminated.

Magnetic system 130-10 includes one or more permanent magnets and/or one or more electromagnets. In at least some examples, magnetic system 130-10 of cleaning system 1000 includes a plurality of magnets (e.g., 1030-1044) located on opposing sides of interior region 1012. The plurality of magnets may include permanent magnets that each generate a persistent magnetic field. Alternatively, or additionally, the plurality of magnets may include electromagnets that each generate a magnetic field responsive to electrical current being supplied to the electromagnets, such as previously described with reference to FIG. 6.

FIG. 11A depicts an example configuration for moving cleaning system 100 of FIG. 1 in relation to example surface 102 of example ferromagnetic object 104. Within FIG. 11A, various features of previously described cleaning system 100 are depicted; however, device body 110 includes one or more mechanical couplings depicted schematically at 1110 and 1112. As an example, mechanical couplings 1110 and 1112 may take the form of rigid or semi-rigid structural members that are capable of transmitting force in both tension and compression directions to device body 110 from one or more remote sources represented schematically at 1120 and 1122. As another example, mechanical couplings 1110 and 1112 may take the form of flexible structural members, such as a cable, chain, belt, or rope that are capable of transmitting force in tension to device body 110 from one or more of remote sources 1120 and 1122. Through operation of remote sources 1120 and/or 1122, device body 110 and its abrasive layer 120 may be translated, rotated, and/or vibrated in relation to surface 102. Remote sources 1120 and 1122 may include electro-mechanical actuators, motors, engines, etc. that are capable of moving device body 110 via mechanical couplings 1110 and 1112. In at least some examples, remote sources may be programmatically controlled by a computing system and/or robotics. It will be further understood that the mechanical couplings and remote sources described with reference to cleaning system 100 may be similarly applied to cleaning system 1000 of FIG. 10.

FIG. 11B depicts another example configuration for moving cleaning system 100 of FIG. 1 in relation to example surface 102 of example ferromagnetic object 104. Within FIG. 11B, various features of previously described cleaning system 100 are depicted; however, device body 110 in this example is self-propelled by an on-board motor 1130 via one or more wheels or treads depicted schematically at 1132. In this configuration, device body 110 may be moved at a user-defined or programmatically-defined speed along surface 102 by on-board motor 1130. On-board motor 1130 may be an electrically-powered motor, an air-powered motor, or a combustion-powered motor from on-board or remotely-connected energy sources. In at least some examples, on-board motor 1130 and/or a steering system associated with one or more wheels or treads 1132 may be user-controlled or programmatically controlled from a remote location by a computing system and/or robotics over a wired or wireless network to clean surface 102. It will be further understood that the on-board motor, steering system, and wheels/treads described with reference to cleaning system 100 may be similarly applied to cleaning system 1000 of FIG. 10.

FIG. 12 is a flow diagram depicting an example method 1200 for cleaning a surface of a ferromagnetic object. Aspects of method 1200 may be performed using any of the cleaning systems disclosed herein, including previously described cleaning system 100 and cleaning system 1000, as examples. It will be understood that method 1200 or portions thereof may be performed by one or more users, one or more machines (including computing system/control system hardware), or by a combination of one or more users and/or machines.

At 1210, the method includes identifying a region of a surface of a ferromagnetic object to be cleaned. As previously described with reference to FIG. 9B, select regions of a surface may be cleaned by operation of cleaning system 100 during a cleaning operation while other regions of the surface are not to be cleaned during the cleaning operation. Within the context of composite layup, for example, regions of a surface of ferromagnetic cure tooling may be coated with a mold-release material that is to be re-used over multiple layup operations, whereas other regions of the surface (e.g., edges of cure tooling to which vacuum bags are taped or adhered) are to be cleaned after each layup operation to remove resin and/or other contaminants.

At 1212, the method includes selecting a cleaning system that includes a device body comprising a magnetic system configured to generate a magnetic field. The cleaning system further includes an abrasive layer that is coupled to the device body. The cleaning system selected at 1212 may include any of the cleaning systems disclosed herein, including cleaning systems 100 and 1000.

In at least some examples, the cleaning systems disclosed herein may be manufactured by forming the device body using injection molding, additive manufacturing (e.g., 3D printing), or machining the device body from one or more pieces of raw material. The device body may be combined with a magnetic system, such as in examples where the device body is formed from a non-magnetic material. In at least some examples, one or more magnets may be permanently incorporated into the device body at the time of molding or additive manufacturing of the device body. An abrasive layer may be mounted to a cleaning face of the device body in the example of cleaning system 100 or to a power tool in the example of the shroud of cleaning system 1000. In at least some examples, an abrasive layer of a particular area, thickness, and/or compressibility (stiffness or resistance to deformation), and so forth, may be selected to adjust a strength of the magnetic field generated by the magnetic system in relation to an exterior-facing surface (e.g., exterior-facing surface 122) of the abrasive layer. For example, selecting an abrasive layer having a smaller area for use with a magnetic field of a certain strength may effectively increase the force per unit area to which the abrasive layer is urged against the ferromagnetic object, as related to an abrasive layer having a larger area with a magnetic field of the same strength. In another example, a thicker and/or less compressible abrasive layer may be selected to reduce the strength of the magnetic field in relation to the exterior-facing surface of the abrasive layer that is urged against a ferromagnetic object, or a thinner and/or more compressible abrasive layer may be selected to increase the strength of the magnetic field in relation to the exterior-facing surface of the abrasive layer that is urged against the ferromagnetic object. This adjustment to the strength of the magnetic field may be used in addition to or as an alternative to any of the other magnetic field adjustment techniques disclosed herein.

As part of selecting the cleaning system at 1212, the method may additionally include, at 1214, selecting the device body from a plurality of available device bodies that is suitable for the region of the surface to be cleaned. For example, a device body, such as device body 110-9 of FIGS. 9A and 9B that includes a guide portion may be selected for a cleaning operation that is limited to region 922 of FIG. 9. As another example, a device body having a convex cleaning face, a concave cleaning face, or a flexible cleaning face, such as described with reference to FIGS. 8A, 8B, and 8C, respectively, may be selected for cleaning ferromagnetic objects having non-planar surfaces.

At 1216, the method includes setting a magnetic field and/or a corresponding magnetic force of the magnetic system. The method at 1216 may include adjusting the strength of the magnetic field generated by the magnetic system in relation to the abrasive layer from a first value to a second value to vary the magnetic force urging the abrasive layer against the surface of the ferromagnetic object. As part of setting the magnetic force of the magnetic system, the method at 1218 may include one or more of: increasing a quantity of permanent magnets by adding one or more permanent magnets to the device body, decreasing a quantity of permanent magnets by removing one or more permanent magnets from the device body, replacing one or more permanent magnets accommodated by the device body, and/or adjusting a positioning of one or more permanent magnets accommodated by the device body in relation to the abrasive layer to achieve a target magnetic field and corresponding magnetic force, such as previously described with reference to the example configurations of FIGS. 2-5. Alternatively or additionally, as part of setting the magnetic force of the magnetic system, the method at 1220 may include varying an electrical current supplied to the one or more electromagnets of the magnetic system to generate a magnetic field having a target strength via the one or more electromagnets.

At 1222, the method includes placing the abrasive layer in contact with the surface. At 1224, the magnetic field generated by the magnetic system urges the abrasive layer against the surface of the ferromagnetic object with a magnetic force corresponding to a strength of the magnetic field.

At 1226, the method includes moving the abrasive layer relative to the surface while the abrasive layer is in contact with and being urged against the surface of the ferromagnetic object by the magnetic field generated by the magnetic system. Movement of the abrasive layer may include translation, rotation, and/or vibration of the abrasive layer relative to the surface. Within the context of cleaning system 100, device body 110 may be moved by hand or via a machine to move abrasive layer 120 relative to the surface. Within the context of cleaning system 1000, power take-off 1024 may be operated via power tool 1020 to move abrasive layer 120 relative to the surface. Cleaning solutions and solvents may be applied to the surface prior to or during cleaning of the surface to aid in the removal of resin and other contaminants. In at least some examples, setting of the magnetic force of the magnetic system previously described at 1216 may be performed while the abrasive layer is in contact with the surface and/or while the abrasive layer is being moved relative to the surface.

FIG. 13 depicts an example abrasive layer 120-13 that is permeable by ferromagnetic particulate or other contaminant particulate produced by cleaning example surface 102 of example ferromagnetic object 104. Abrasive layer 120-13 is a non-limiting example of previously described abrasive layer 120 of FIG. 1. In this example, ferromagnetic particulate and contaminant particulate 1310 cleaned from surface 102 by abrasive layer 120-13 permeate the abrasive layer material toward device body 110. Indeed, magnetic field 132 generated by magnetic system 130 may attract and capture ferromagnetic particulate during a cleaning operation. In at least some examples, abrasive layer 120-13 may take the form of a porous matrix material. As non-limiting examples, abrasive layer 120-13 may take the form of a flexible, woven or non-woven, fiber matrix formed of silicon carbide, aluminum oxide, talc abrasive mineral, polymer (e.g., nylon, polypropylene, etc.), or other suitable material.

FIG. 14 depicts an example abrasive layer 120-14 that is permeable by ferromagnetic particulate or contaminant particulate produced by cleaning a surface of a ferromagnetic object. In this example, ferromagnetic particulate and contaminant particulate 1410 cleaned from the surface by abrasive layer 120-14 permeate openings 1412 formed within the abrasive layer material. The use of openings 1412 within the abrasive layer material may enable particulate to pass through the abrasive layer while using materials that are non-porous, such as sandpaper, as an example.

Examples of the subject matter of the present disclosure are described in the following enumerated paragraphs.

A1. A cleaning system for cleaning a surface of a ferromagnetic object, the cleaning system comprising: a device body defining a cleaning face having an abrasive layer configured for selective placement against the surface, the device body comprising a magnetic system configured to generate a magnetic field of a strength that is adjustable in relation to the abrasive layer, wherein the magnetic field generated by the magnetic system is configured to urge the abrasive layer against the surface of the ferromagnetic object with a magnetic force corresponding to the strength of the magnetic field.

A2. The cleaning system of paragraph A1, wherein the magnetic system includes a plurality of magnets; wherein the device body further defines one or more receptacles or mounts that accommodate one or more select magnets of the plurality of magnets; and wherein the one or more select magnets accommodated by the one or more receptacles or mounts are removable from the one or more receptacles or mounts of the device body.

A3. The cleaning system of any of paragraphs A1-A2, wherein the device body is formed of a non-magnetic material.

A4. The cleaning system of paragraph A2, wherein the plurality of magnets include at least a first magnet and a second magnet; wherein a strength of a magnetic field generated by the first magnet differs from a strength of a magnetic field generated by the second magnet; and wherein the strength of the magnetic field generated by the magnetic system is adjustable by replacement of the first magnet with the second magnet at a receptacle or mount of the device body.

A5. The cleaning system of paragraph A2, wherein the strength of magnetic field generated by the magnetic system is adjustable by increasing or decreasing a quantity of the plurality of magnets accommodated by the one or more receptacles or mounts of the device body, or by adjusting a positioning of one or more of the plurality of magnets in relation to the abrasive layer.

A6. The cleaning system of any of paragraphs A1-A5, wherein the magnetic system includes: one or more electromagnets; and an electronic controller that varies electrical current supplied to the one or more electromagnets to adjust the strength of the magnetic field responsive to a user input.

A7. The cleaning system of any of paragraphs A1-A6, wherein the electronic controller maintains the strength of the magnetic field at a constant strength following adjustment of the strength of the magnetic field responsive to the user input.

A8. The cleaning system of any of paragraphs A1-A7, wherein the abrasive layer is permeable by ferromagnetic particulate produced from the surface of the ferromagnetic object.

A9. The cleaning system of any of paragraphs A1-A8, wherein the abrasive layer is mounted to and removable from the cleaning face of the device body.

A10. The cleaning system of any of paragraphs A1-A9, wherein the device body includes a guide portion projecting outward from a first edge of the cleaning face to form an interior-facing corner with the cleaning face.

A11. The cleaning system of any of paragraphs A1-A10, wherein the device body includes one or more handles configured to enable a user to move the abrasive layer of the cleaning face relative to the surface.

B1. A method for cleaning a surface of a ferromagnetic object, the method comprising: selecting a cleaning system that includes a device body comprising a magnetic system configured to generate a magnetic field, the device body coupled to an abrasive layer configured for selective placement against the surface; placing the abrasive layer in contact with the surface with the magnetic field generated by the magnetic system urging the abrasive layer against the surface of the ferromagnetic object with a magnetic force corresponding to a strength of the magnetic field; and moving the abrasive layer relative to the surface while the abrasive layer is in contact with the surface.

B2. The method of paragraph B1, further comprising: adjusting the strength of the magnetic field generated by the magnetic system in relation to the abrasive layer from a first value to a second value to vary the magnetic force urging the abrasive layer against the surface of the ferromagnetic object.

B3. The method of any of paragraphs B1-B2, wherein the device body defines one or more receptacles or mounts that accommodate one or more permanent magnets; and wherein adjusting the strength of the magnetic field includes adding, removing, replacing, or adjusting a positioning of one or more permanent magnets accommodated by the one or more receptacles or mounts.

B4. The method of any of paragraphs B1-B3, wherein the magnetic system includes: one or more electromagnets; and wherein adjusting the strength of the magnetic field includes varying electrical current supplied to the one or more electromagnets.

C1. A cleaning system for cleaning a surface of a ferromagnetic object, the cleaning system comprising: a device body forming a shroud mountable to a power tool that includes a power take-off element, the shroud defining an interior region that is configured to accommodate and partially surround the power take-off element; wherein the shroud comprises a magnetic system configured to generate a magnetic field urging a distal end of the power-take-off element toward the surface of the ferromagnetic object with a magnetic force corresponding to a strength of the magnetic field.

C2. The cleaning system of paragraph C1, wherein the shroud includes a plurality of magnets of the magnetic system located on opposing sides of the interior region.

C3. The cleaning system of paragraph C2, wherein the plurality of magnets include permanent magnets that each generate a persistent magnetic field.

C4. The cleaning system of paragraph C2, wherein the plurality of magnets include electromagnets that each generate a magnetic field responsive to electrical current being supplied to the electromagnets.

C5. The cleaning system of any of paragraphs C1-C4, further comprising: the power tool mounted to the shroud with the power take-off element accommodated by the interior region; and an abrasive layer mounted to the distal end of the power take-off element.

The present disclosure includes all novel and non-obvious combinations and subcombinations of the various features and techniques disclosed herein. The various features and techniques disclosed herein are not necessarily required of all examples of the present disclosure. Furthermore, the various features and techniques disclosed herein may define patentable subject matter apart from the disclosed examples, and may find utility in other implementations not expressly disclosed herein. 

1. A cleaning system for cleaning a surface of a ferromagnetic object, the cleaning system comprising: a device body defining a cleaning face having an abrasive layer configured for selective placement against the surface, the device body comprising a magnetic system configured to generate a magnetic field of a strength that is adjustable in relation to the abrasive layer, wherein the magnetic field generated by the magnetic system is configured to urge the abrasive layer against the surface of the ferromagnetic object with a magnetic force corresponding to the strength of the magnetic field.
 2. The cleaning system of claim 1, wherein the magnetic system includes a plurality of magnets; wherein the device body further defines one or more receptacles or mounts that accommodate one or more select magnets of the plurality of magnets; and wherein the one or more select magnets accommodated by the one or more receptacles or mounts are removable from the one or more receptacles or mounts of the device body.
 3. The cleaning system of claim 2, wherein the device body is formed of a non-magnetic material.
 4. The cleaning system of claim 2, wherein the plurality of magnets include at least a first magnet and a second magnet; wherein a strength of a magnetic field generated by the first magnet differs from a strength of a magnetic field generated by the second magnet; and wherein the strength of the magnetic field generated by the magnetic system is adjustable by replacement of the first magnet with the second magnet at a receptacle or mount of the device body.
 5. The cleaning system of claim 2, wherein the strength of magnetic field generated by the magnetic system is adjustable by increasing or decreasing a quantity of the plurality of magnets accommodated by the one or more receptacles or mounts of the device body, or by adjusting a positioning of one or more of the plurality of magnets in relation to the abrasive layer.
 6. The cleaning system of claim 1, wherein the magnetic system includes: one or more electromagnets; and an electronic controller that varies electrical current supplied to the one or more electromagnets to adjust the strength of the magnetic field responsive to a user input.
 7. The cleaning system of claim 1, wherein the electronic controller maintains the strength of the magnetic field at a constant strength following adjustment of the strength of the magnetic field responsive to the user input.
 8. The cleaning system of claim 1, wherein the abrasive layer is permeable by ferromagnetic particulate produced from the surface of the ferromagnetic object.
 9. The cleaning system of claim 1, wherein the abrasive layer is mounted to and removable from the cleaning face of the device body.
 10. The cleaning system of claim 1, wherein the device body includes a guide portion projecting outward from a first edge of the cleaning face to form an interior-facing corner with the cleaning face.
 11. The cleaning system of claim 1, wherein the device body includes one or more handles configured to enable a user to move the abrasive layer of the cleaning face relative to the surface.
 12. A method for cleaning a surface of a ferromagnetic object, the method comprising: selecting a cleaning system that includes a device body comprising a magnetic system configured to generate a magnetic field, the device body coupled to an abrasive layer configured for selective placement against the surface; placing the abrasive layer in contact with the surface with the magnetic field generated by the magnetic system urging the abrasive layer against the surface of the ferromagnetic object with a magnetic force corresponding to a strength of the magnetic field; and moving the abrasive layer relative to the surface while the abrasive layer is in contact with the surface.
 13. The method of claim 12, further comprising: adjusting the strength of the magnetic field generated by the magnetic system in relation to the abrasive layer from a first value to a second value to vary the magnetic force urging the abrasive layer against the surface of the ferromagnetic object.
 14. The method of claim 12, wherein the device body defines one or more receptacles or mounts that accommodate one or more permanent magnets; and wherein adjusting the strength of the magnetic field includes adding, removing, replacing, or adjusting a positioning of one or more permanent magnets accommodated by the one or more receptacles or mounts.
 15. The method of claim 12, wherein the magnetic system includes: one or more electromagnets; and wherein adjusting the strength of the magnetic field includes varying electrical current supplied to the one or more electromagnets.
 16. A cleaning system for cleaning a surface of a ferromagnetic object, the cleaning system comprising: a device body forming a shroud mountable to a power tool that includes a power take-off element, the shroud defining an interior region that is configured to accommodate and partially surround the power take-off element; wherein the shroud comprises a magnetic system configured to generate a magnetic field urging a distal end of the power-take-off element toward the surface of the ferromagnetic object with a magnetic force corresponding to a strength of the magnetic field.
 17. The cleaning system of claim 16, wherein the shroud includes a plurality of magnets of the magnetic system located on opposing sides of the interior region.
 18. The cleaning system of claim 17, wherein the plurality of magnets include permanent magnets that each generate a persistent magnetic field.
 19. The cleaning system of claim 17, wherein the plurality of magnets include electromagnets that each generate a magnetic field responsive to electrical current being supplied to the electromagnets.
 20. The cleaning system of claim 16, further comprising: the power tool mounted to the shroud with the power take-off element accommodated by the interior region; and an abrasive layer mounted to the distal end of the power take-off element. 